a problem about data persistence when the nifi server deployed on k8s

[Shigin Wang]

the diroctories has been mounted as below:

```

volumeMounts:
  - name: volume-0
    mountPath: /opt/nifi/nifi-current/flowfile_repository
    subPath: flowfile_repository
  - name: volume-0
    mountPath: /opt/nifi/nifi-current/content_repository
    subPath: content_repository
  - name: volume-0
    mountPath: /opt/nifi/nifi-current/provenance_repository
    subPath: provenance_repository
  - name: volume-0
    mountPath: /opt/nifi/nifi-current/database_repository
    subPath: database_repository
  - name: volume-0
    mountPath: /opt/nifi/nifi-current/state
    subPath: state
  - name: volume-0
    mountPath: /opt/nifi/nifi-current/logs
    subPath: logs
  - name: volume-0
    mountPath: /opt/nifi/nifi-current/work
    subPath: work
  - name: nifi-config
    mountPath: /opt/nifi/scripts/start.sh
    subPath: start.sh
  - name: nifi-config
    mountPath: /opt/nifi/nifi-current/conf/bootstrap.conf
    subPath: bootstrap.conf

```


but data in nifi would be disappeared after restarted!